Drycleaning and fluid decontamination apparatus and method



May 12, 1970 y M. R.. EsTABRooK 3,510,890

DRYCLEANING AND FLUID DECONTAMINATION APPARATUS AND METHOD Filed Sept. 17, 1968 2 Shee'cs-Sheeil l May 12, 1970 M R, ESTABROOK 3,510,890

DRYCLEANING AND FLUID DECONTAMINATION APPARATUS AND4 METHOD JZ/proof QZ; M4 #$6 MQ United States Patent O 3,510,890 DRYCLEANING AND FLUID DECONTAMINA- TION APPARATUS AND METHOD Mark R. Estabrook, Rockford, Ill., assignor to Barnes Drill Co., Rockford, Ill., a corporation of Illinois Continuation-in-part of application Ser. No. 741,522, July 1, 1968. This application Sept. 17, 1968, Ser. No. 767,036

Int. Cl. B01d 37/04; D06f 39/10, 43/08 U.S. Cl. 8-158 9 Claims ABSTRACT OF THE DISCLOSURE A drycleaning and fluid decontamination apparatus including a washer, a Hydroclone separator, a bank of filter and chemical cartridges for final cleaning of the separator, a pump, and flow control valves and pipes for routing the fluid normally from the separator forwardly through the bank to the washer and back to the separator. During unloading and reloading of the washer, fluid is routed from the separator reversely through the bank and back to the separator to backwash the cartridges and remove collected solids from the system. An option by-passes the forward flow through the bank around the washer upon resumption of forward flow through the bank for removal of solids deposited on the output sides of the cartridges.

CROSS {REFERENCE TO A RELATED APPLICATION rIlhis application is a continuation-impart of my copending application Ser. No. 741,522, filed July l, 1968, and now abandoned.

BACKGROUND OF THE INVENTION This invention relates generally to the cleaning or decontamination of fluid in an apparatus in which fluid is circulated repeatedly through a work station, picks up contamination in the Work station, and is cleaned prior to recirculation, and relates specifically to such `an apparatus in which initial cleaning of the fluid is accomplished with a Hydroclone separator for removing larger solid particles, and final cleaning or polishing is accomplished by passing the pre-cleaned fluid through one or more final cleaners, preferably in cartridge form and including at least one filter for collecting solid particles that have been passed by the Hydroclone.

The invention has particular reference to a drycleaning apparatus in which the work station is a so-called washer where drycleaning fluid or solvent is passed through a batch of articles to be cleaned, and is circulated through the decontaminating portion of the apparatus for cleaning of the fluid after each pass through the washer and preparatory to recirculation through the apparatus. Filter cleaners have been used in this environment, along with chemical cleaners for removing dissolved contaminants, but the limited life of the cleaners due to clogging by collected solids has been a problem in operation, making the operating cost somewhat higher and requiring more frequent attention from the operator than had been anticipated.

SUMMARY OF THE INVENTION The primary object of the invention is to provide a new and improved method and apparatus yfor decontaminating such fluid and, Iat the same time, substantially increasing the service life of the final cleaners used, thereby reducing both the cost of cleaners in operation and the time and labor required for replacement of spent cleaners. A more detailed object is to use 'the available components of the apparatus to remove collected particles periodically from the cleaners to renew the latter 3,510,890 Patented May 12, 1970 ice BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary side elevational view of a drycleaning and fluid-decontaminating apparatus embodying the novel features of the present invention.

FIG. 2 is a schematic view similar to FIG. l and illustrating the normal routing of fluid through the apparatus.

FIG. 3 is another schem-atic View illustrating the alternate routing of fluid for renewal of the final cleaners.

DETAILED DESCRIPTION As shown in the drawings for purposes of illustration, the invention is embodied in a cleaning apparatus for circulating fluid through a work station 10 such as a conventional drycleaner, hereafter called the washer, and decontaminating the fluid iafter passage through the washer by passing the fluid first through a Hydroclone separator 11 for removal of larger solid contamination particles and then through one or more final cleaning elements for final cleaning and polishing of the fluid before it is recycled through the washer. Herein. the final cleaning elements are arranged in a bank 12 of cartridges including two cartridges 13 of filter paper for straining out solid particles passed by the Hydroclone, and also one chemical cartridge 14 for removing dissolved contaminants such as grease and dyes.

Hydroclones suitable for use with the invention are known in fthe art, the illustrative Hydroclone 11 having a conical treating chamber 15 in a body 17 into which dirty fluid from a reservoir 18 is introduced by a pump 19 through lan inlet pipe 20', herein into a cylindrical eX- tension 21 on the larger end of the chamber 15, to create a vortical flow of fluid toward the smaller end of the chamber. An underflow outlet at 22 opens through an inverted subcone 23 into an underflow chamber shown at 24, this chamber being connected by a pipe 25 to the inlet 27 of an underflow pot 28. In a m-anner well known in the art, the Hydroclone separates solid particles from the fluid and produces a reverse flow of clean fluid up- Wardly toward the larger end of the conical chamber and out through an outlet pipe 29. 'The separated solid particles pass downwardly through the underflow chamber 24 to the underflow pot 28 and preferably are collected in a removable fil-ter bag (not shown), the accompanying fluid being drained through a pipe 30 back to the fluid reservoir 18 of the apparatus.

Although Hydroclones are highly effective in removing solid particles from fluid, a relatively small percentage of the total solid contamination passes through the Hydroclone 17, particularly particles in the smaller size ranges, and leaves the separator with the output flow in the pipe 29. The filter cartridges 13 have papers capable of collecting virtually all particles above a selected size so that the flow out of the filters is of closely controlled cleanliness with repect to the `size of any entrained solid particles. The chemical cartridge 14 has a chemical bed such as activated charcoal capable of removing dissolved contaminants from the flow through the bed, and is included for removal of free dyes from fabrics in the work chamber and other soluble contamination.

It will be seen in the drawings that the cartridge bank 12 is fed by a single branch 3.1 from the output pipe 29 and that the three cartridges are connected in parallel between this branch and a pipe 32 leading to the washer 10. A manifold 33 divides the output of the Hydroclone 11 into three flows which enter the outer portions of the respective cartridges, pass through the paper or chemical therein, and then exit through center passages 34 in the cartridges connected through three outlets 35 to the pipe 32. Thus, only part of the output flow passes through each cartridge, and all of the flows are combined to pass through the washer. It has been found that this division is practical in -service use, and that the repeated cycling of the fluid through the system results in satisfactory filtering and chemical treatment of the whole body of fluid circulating in the apparatus.

After passing through the washer and a batch of articles therein, the fluid returns to the reservoir 18 through a pipe 37 for recycl-ing through the decontaminating apparatus by the pump 19. Initially, the fluid picks up a substantial amount of contamination during each pass through the washer, but the amount becomes progressively smaller as the operation continues, until finally the articles attain the desired degree of cleanliness and the operation -is terminated. This preferably is set up on a timed cycle which experience lindicates is long enough to accomplish the desired result.

The service life of the filter cartridges 13 depends upon the concentration of solids in the Hydroclone output, the resultant rate of build-up of solids in cakes on the outer sides of the filter papers, and the clogging of the pores of the paper by the solids. Since part of the Hydroclone output also passes through the charcoal cartridge 14, this cartridge also is subject to clogging by accumulated solids. It will be evident that replacement of cartridges is a substantial factor in the operating cost of the apparatus and, in a commercial drycleaning establishment, this is a primary area of concern, both as to cost of cartridges and as to labor and down time required for servicing of the apparatus.

The present invention contemplates a novel apparatus and method for decontaminating fluid that significantly increase the service life of the cleaners by periodically removing collected solids from the upstream sides of the cleaning elements with a reverse flow of fluid for backwashing the elements, and returning this reverse flow, together with the collected solids, through the Hydroclone 11 for separation of the solids and removal of the same from the system. Moreover, the renewal of the cleaning elements is accomplished during recurring inactive periods in the use of the apparatus, the unloading and loading periods in a drycleaning apparatus, to avo1d interference with normal service use of the apparatus.

In this instance, the normal route of flu-id from the Hydroclone 11 is as previously described, passing through the bank 12 of cartridges to the washer 10 and then back to the reservoir 18 for recirculation, and an alternate route is defined by a pipe 38 connecting the output pipe 29 through a normally closed valve 39 to the pipe 32 normally receiving the output of the cartridges. A normally open valve 40 is interposed in the pipe 32 between the washer and the cartridges, and a second normally open valve 41 is interposed in the output pipe 29 upstream from the inlet 31 of the cartridge bank. A normally closed valve 42 is placed in an extension 43 of the output pipe 29 beyond the cartridge bank connecting the output pipe to the intake pipe 44 extending between the pump 19 and the reservoir 18. These four valves are selectively operable to change the fluid routing from the normal, service route to the alternate, backwashing route and back to the normal route when backwashing 4is completed.

As shown in FIG. 2, representing the normal routing, the valve 41 in the output pipe 29 is open and the valve 39 in the connecting pipe 38 is closed so that all fluid from the Hydroclone 11 must flow from the output pipe to the bank 12 of cartridges. The valve 42 in the extension 43 is closed, forcing all the flow through the bank to the pipe 32 to the washer 10, and the valve 40 is open to pass this flow into the washer and thence back to the reservoir 18.

With a fresh batch of articles to be cleaned in the washer 10 and the valves set for the normal flow, operation of the pump 19 results in a continuous flow of clean fluid through the washer, injection of dirty fluid into the Hydroclone 11, passing of precleaned fluid through the cartridge bank 12, and return of finally cleaned and polished fluid through the washer to continue removing contamination from the batch in a continuous and repeating cycle until the articles have been cleaned to the extent desired. Accompanying the cleaning of the articles, of course, is a continuous removal of most of the solid contamination by the Hydroclone, filtering of additional solid contamination by the filter cartridges 13, and removal of dissolved contamination (and some incidental filtering of solids) by the charcoal cartridge 14.

At the end of the normal cleaning cycle, for example, after a timed interval of fifteen to thirty minutes, the flow to the washer 10 is terminated, the bulk of the iluid remaining in the washer is dumped, and the remainder of the fluid is extracted by spinning so that the cleaned articles may be removed for insertion of a new batch. Herein, the termination of cleaning is accompanied by switching to the alternate fluid routing (FIG. 3), the valve 41 being closed to stop forward flow to the cartridge bank 12, the valve 39 being opened to admit fluid through the connecting pipe 38 to the outlets 3S of the bank, the valve 40 being closed to block flow to the washer, and the valve 42 being opened to permit the reverse flow of fluid from the bank to return to the intake pipe 44 between the pump 19 and the reservoir 18.

Since the pump 19 may continue to run, the clean out` put of the Hydroclone 11 is forced through the outlet pipes 35 into the center passages 34 of the cartridges to flow outwardly through all three cartridges. This reverse flow dislodges all free solids collected on the other sides of the cleaning elements and flushes the particles out through the manifold 33 and the pipe 31 to the extension 43, and thence into the pump intake pipe 44.

Accordingly, the collected particles removed from the cleaning elements are routed `back through the Hydroclone 11 and are removed from the backwash fluid, which continues to flow reversely through the cartridge bank 12 until the valves 39, 40, 41 and 43 are returned to normal condition, for example, for five to ten minutes. The period of time is the normal free time during dumping, extraction, unloading and reloading, so that backwashing may be completed to a satisfactory extent by the time that the washer 10 is ready to resume operation with the valves in the condition shown in FIG. 2. Of course, the cleaning elements selected must have sufficient strength to withstand both forward and reverse flows of fluid at the output pressure of the hydroclone 11.

An important aspect of the invention is based on the discovery that the use of the cartridges 13 with the Hydroclone 11 together with the backwashing of the cartridges materially increases the effectiveness of the Hydroclone in removing the fine particles from the fluid. Thus, as is characteristic of this type of separator, the Hydroclone 11 is quite effective in removing relatively large particles and the effectiveness of the Hydroclone decreases as regards finer particles. As a result, the very fine particles pass through the outlet of the Hydroclone and collect on the cartridges. It has been found that a significant number of these fine particles join together in groups as agglomerates which, in effect, are the same as particles of a larger size. When the cartridges are backwashed, therefore, the

agglomerates are readily removed from the fiuid during the next fiow through the Hydroclone.

The control valves 39, 40, 41 and 43 may take different well-known forms, one satisfactory type being pressureactuated sleeve-type valves in which actuating fluid such as air under pressure from a common source (not shown) is introduced through pilot lines 45 (FIG. 1) to close the valves, the pressure being released to open the valves. Such valves are sold by Airmatic Valve, Inc. under the trademark Tube-O-Matic. The pump 19 preferably is of the centrifugal type capable of delivering contaminated fiuid under the optimum pressure for the particular Hydroclone 11 used. Design parameters of Hydroclones vary in known manner with the particular fluids and contaminants being handled, and do not form a part of the present invention.

It will be apparent that the reverse flow of backwashing fluid may deposit a coating of small particles on the inner sides of the cleaning elements, and that these coatings will be discharged, at least in part, toward the washer when the normal fiow is resumed. While such a discharge is not necessarily harmful to the dirty articles in the Washer, and will be removed as the fluid again passes through the washer and the bank, an optional by-pass line may be provided to continue by-passing the washer after resumption of the normal fiow through the bank until the inside coating has been cleared away. This line is illustrated in FIG. 3 in dot-dash lines at 47, and includes a valve 48 which will be opened at the beginning of forward flow through the bank, the valve 40 remaining closed so that the initial, flushing flow is returned through line 47 to the reservoir 18. After a short interval, the valve 47 is closed and the valve 40 is opened, thereby resuming the flow through the washer.

From the foregoing, it will be seen that the present invention provides a practical method and apparatus for significantly extending the useful life of the final cleaning elements and using the existing separator 11 of the apparatus for removing the collected solids from the system before those solids are returned to the final cleaning elements 13, 14 after resumption of normal operation. In a commercial drycleaning installation, for which the apparatus and method were designed, the result is a material reduction in operating costs without interference with normal operation and without substantial additional cost of equipment.

I claim as my invention:

1. A drycleaning apparatus having, in combination, a washer for holding a batch of articles to be cleaned, a Hydroclone separator, a final cleaning bank including at least one filter for collecting particles passed by said separator; a pump for feeding fiuid to and through said separator; means defining a normal route for the fluid from said pump through said separator, then through said bank and said washer, and then back to said separator for repetitive recirculation through said apparatus; means defining an alternate route for the fluid from said pump through said separator, reversely through said bank and back through said separator, by-passing said washer; and selectively operable ow means for controlling the circulation of said iiuid rst along said normal route for cleaning of a batch of articles in said drycleaner, removal of solid particles by said separator, and collection of passed particles by said bank, and then along said alternate route for cleaning of said bank for reuse in a subsequent cycle and accompanying removal of collected particles -by said Hydroclone before resumption of circulation along said normal route to clean another batch of articles.

2. A drycleaning apparatus as defined in claim 1 in which said flow means return the fluid from said bank directly to said pump during circulation along said alternate route.

3A drycleaning apparatus as defined in claim 1 in which said iiow means direct fluid from said bank directly to said washer upon resumption of circulation along said normal route.

4. A drycleaning appara-tus as defined in claim 11 in which said liow means include a -line for by-passing fluid from said bank around said Washer upon resumption of forward fiow through said bank, and valving for directing the fluid to said washer after a selected interval of such by-passing.

5. Apparatus for decontaminating fluid contaminated as the fluid fiows through -a work station, said apparatus having, in combination, a Hydroclone separator, a final cleaning bank including at least one lter for collecting particles passed by said separator, a pump for feeding uid to and through said separator; means defining a normal route for the fluid from said pump through said separator, then through said bank and said station, and then back to said separator lfor repetitive recirculation through said apparatus; means defining an alternate route for the fiuid from said pump through said separator, reversely through said bank and back through said separator, by-passing said station; and selectively operable fiow means for controlling the circulation of said fiuid first along said normal route through said station, removal of solid particles by said separator, and collection of passed particles by said bank, and then along said alternate route for cleaning of said bank for reuse in a subsequent cycle and accompanying lremoval of collected particles by said Hydroclone before resumption of circulation along said normal route through said station.

6. The method of drycleaning ba-tches of articles in a drycleaning apparatus including a washer, a Hydroclone separator, a bank of final cleaning elements including at least one filter, and means for circulating fluid through said appara-tus, said method including the steps of, passing fluid through said washer and a first batch of articles therein, then through said separator for removal of solid particles of contamination, and then through said bank for final cleaning including filtering of smaller particles passed by said separator; returning fiuid from said bank to said Washer and continuing such circulation through the apparatus until the batch is substantially clean; termina-ting the fiow of fiuid through said washer while directing the flow from said separator reversely through said bank to backwash the final cleaning elements, an-d returning the reverse flow through said bank to said separator for removal of solid particles from the backwa-shing ow; removing said first batch of ar-ticles from said washer and inserting a second batch prior to resuming the passage of uid through the washer; and terminating said backwashing flow and resuming -t-he initial flow to clean said second batch, remove solid particles from the fluid after passage through said washer, and final clean the fluid from said separator with said cleaning elements prior to returning the fluid through said washer.

7. The method defined yin claim 6 in which said backwashing ow is initiated upon Itermination of the fiow through said washer and continued through removal of said first batch and insert-ion of said second batch, and is terminated as soon as said second batch is ready for cleaning.

8. The method of decontaminating fluid in an apparatus including -a work station, a Hydroclone separator, means for circulating fiuid under pressure through said separator for removal of solid particles from the fiuid and through said station for reuse, and a filter yfor finalcleaning the fluid output of said separator, said method comprising the steps of, passing fluid through said station, -said separator and said filter in a continuous and repetitive cycle whereby larger solid particles of contamination from said fiuid are removed by said separator, other contaminants including smaller solid particles are removed by said filter, :and clean fluid `is passed back through the station and then recirculated for decontamination, terminating circulation of fluid through said station, reversing the flow from said separator through said filter to by-pass said station and wash accumulated solids from the filter, and passing the rever-se iiow from said filter back through said separator for removal of said accumulated solids from the fluid =by the separator.

9. The method of decontaminating fluid in an -apparatus Iincluding a work station, a Hydroclone separator, means for circulating uid under pressure through said separator for removal of solid particles from the uid and through said station for reuse, and a filter for final-cleaning the fiuid output of said separator, said method comprising the steps of, passing fluid through said station, said separator and said filter in a continuous and repetitive cycle thereby separating larger solid particles of contamination from said uid by said separator, collecting smaller solid particles by said filter, and passing clean fluid back through the station, at least some of the smaller particles collected on said filter joining together `in groups to form agglomerates, terminating circulation of fluid 8 through said station, reversing the flow from said separator through said filter to by-pass said station and wash accumulated solids and said .agglomerates from the filter, and passing 4the reverse flow from said filter back through said separator for removal of said accumulated solids and agglomerates from the fluid by the separator.

References Cited UNITED STATES PATENTS 2,044,096 6/1936 Moran 68-18 X 2,075,010 3/1937 Angelus et al. 68-18 3,291,562 12/1966 Anderson 210-167 X WILLIAM I. PRICE, Primary IExaminer U.S. Cl. X.R. 

